Crystal oscillator

Abstract

A crystal oscillator that outputs an oscillation output signal of an oscillator circuit oscillated by a crystal resonator as a resonation source via a buffer circuit, includes: a plurality of waveform output circuits provided in the buffer circuit, each converting, when inputted, the oscillation output signal into a different waveform and outputting the converted signal; a circuit selection switch that selects any one of the plurality of waveform output circuits as a waveform output circuit of the buffer circuit; and a memory circuit that stores data used by the circuit selection switch to select any one of the waveform output circuits.

1. A crystal oscillator that outputs an oscillation output signal of an oscillator circuit oscillated by a crystal resonator as a resonation source via a buffer circuit, comprising:
 a plurality of waveform output circuits provided in the buffer circuit, each converting, when inputted, the oscillation output signal into a different waveform and outputting the converted signal; 
 a circuit selection switch that selects any one of the plurality of waveform output circuits as a waveform output circuit of the buffer circuit; and 
 a memory circuit that stores data used by the circuit selection switch to select any one of the waveform output circuits. 
 
   
   
     2. The crystal oscillator according to  claim 1 , wherein:
 the oscillator circuit includes a voltage control oscillator circuit having a voltage variable capacitance element and a temperature-compensating voltage generator circuit that performs temperature compensation using the voltage variable capacitance element; and 
 the memory circuit stores temperature compensation data used to compensate the temperature characteristics of the crystal resonator. 
 
   
   
     3. The crystal oscillator according to  claim 1 , wherein the crystal oscillator is composed at least of the oscillator circuit, the buffer circuit, the circuit selection switch, and the memory circuit loaded on one chip.